OWINGS MILLS, Md. — Much of the credit for the San Francisco 49ers’ 9-1 start has been bestowed upon their impressive defensive in leading the once-proud franchise to its first winning season since 2002.

However, new head coach Jim Harbaugh has transformed a once-inept offense into an efficient, improving unit taking advantage of the enviable positions presented by a defense that leads the NFL with 26 takeaways. As a result, the 49ers have used their league-best average starting field position to average 25.6 points per game, tied for seventh in the NFL with the Ravens. San Francisco ranked 24th in points per game (19.1) last season. The 49ers have also done an excellent job taking care of the football, tied with Houston with a league-low nine turnovers this season.

The 49ers’ formula for offensive success is no secret: feed the ball to Frank Gore as much as possible. The seventh-year back is third in the NFL in rushing attempts and has 870 yards on the ground this season to pace San Francisco’s sixth-ranked rushing offense.

“He is very special,” linebacker Terrell Suggs said. “He runs angry. He runs very aggressive. We like that. We like the rough stuff.”

Even with the league’s fifth-best run defense, the Ravens could find their hands full trying to fend off a tough San Francisco offensive line — especially on the left side with tackle Joe Staley and guard Mike Iupati — wanting to control the line of scrimmage. And with Ray Lewis’ status for Thursday night remaining a mystery, Baltimore could once again be without its defensive leader.

On the surface, the 49ers’ passing game appears to be the Achilles heel of an otherwise impressive 9-1 team, but the Ravens are looking beyond their low ranking and seeing a far more efficient aerial attack than the numbers indicate.

“Sometimes stats can be deceiving a little bit,” cornerback Chris Carr said. “A lot of times you’ll have teams that have to come from behind and so they have to throw the ball a lot and they get a lot of passing yards. With San Francisco, they’ve been in the lead in a lot of games so they’re going to run the ball and they’re not going to have to throw the ball downfield as much. And so even though they rank 27th [in the NFL], it’s kind of deceiving.”

The numbers aren’t gaudy, but former No. 1 overall pick Alex Smith has experienced a renaissance under Harbaugh and new offensive coordinator Greg Roman. After widely being considered a failure in his first six years in San Francisco, Smith has a 93.9 quarterback rating and is tied among starting quarterbacks with a league-low four interceptions.

The perception of Smith being a game manager in the 49ers offense may have been true in the early weeks of the season, but he has posted five straight weeks of increased passing yards, with six touchdowns and three interceptions over the stretch of time.

Smith is finally showing a few glimpses of what the 49ers saw when they selected him with the first pick of the 2005 draft out of the University of Utah despite his 75.5 career quarterback rating.

“The games that we have watched, he looks like he can throw it to me,” Ravens coach John Harbaugh said. “He is making every single throw. He is making the throws on the deep sideline, from one hash to the other hash. He is making throws downfield. It is very much a downfield passing attack.”

While only averaging 188.3 passing yards per game, Smith has plenty of viable options to target, including tight end Vernon Davis (five touchdowns) and wide receivers Michael Crabtree (455 receiving yards) and Braylon Edwards. Though not robust in its production, the Baltimore defense sees a passing offense capable of giving different looks and making low-risk plays with positive results.

“I think their scheme is the best offense we’ve seen so far this year,” Carr said. “They have multiple sets and they can get in three tight end sets and can run four receivers down the field. They have all the concepts in every single formation so they really keep you off balanced. They shift a lot and get teams confused. I think that’s one of the reason [Smith’s] been so successful. He’s not trying to throw the ball into tight spots too much. He takes what the defense gives him. He knows that their defense is playing really well. He’s playing like a veteran quarterback, very smart. With their players and their scheme, it’s very difficult for a defense because there is a lot to prepare for.”

However, the 49ers will have plenty to prepare for in facing the fourth-ranked defense in the league. With or without Lewis in the lineup, San Francisco may have to turn in its best offensive performance of the season to hand the Ravens their first home loss in 2011.

“This is going to be a dogfight,” Suggs said. “Like I said, I don’t think they could have picked a better game of the season [for Thanksgiving night].”